Pumpable epoxy resin composition

ABSTRACT

An epoxy resin composition curable to a hard impermeable solid which contains a liquid aromatic diluent having the general formula: 
     
         C.sub.6 (R.sub.1).sub.6 
    
     wherein R 1  is hydrogen; a straight or branched chain alkyl radical; a cycloparaffin radical or a mixture thereof; wherein the alkyl and cycloparaffin radicals have within the range of about 1 to 10 carbon atoms; and further wherein at least one R 1  group is said alkyl or cycloparaffin radical.This is a division of application Ser. No. 371,100 filed June 18, 1973.

Liquid waste from industrial plants is being disposed of by injectingthe liquid waste into subterranean formations. Subterranean formationssuitable for accepting liquid waste accept large volumes of waste andare generally separated by natural barriers from formations containingpotable water or useful fluids such as oil and gas.

Some of the liquid waste which is disposed of in subterranean formationsis corrosive to the steel and the hydraulic cement which is commonlyused in the completion of well bores penetrating subterraneanformations. In one method of completing well bores penetratingsubterranean formations a steel conduit is placed in the well bore and ahydraulic cement sealing composition is placed between the conduit andthe well bore to isolate the zones traversed by the well bore. Anexample of corrosive liquid waste being disposed of in this manner isacidic liquid waste from steel pickling baths. Acid can corrode steel tothe point of failure and can dissolve hydraulic cement. If this happens,the liquid waste could be injected into a zone containing potable wateror other useful fluids.

Well bores through which liquid waste is injected into subterraneanformations should be completed with materials which will not be corrodedby flowing the liquid waste through the well bore. Epoxy resin has beenfound to be resistant to degradation by liquid waste containing manyorganic and inorganic compounds.

To use epoxy resin for the completion of liquid waste disposal wells,the epoxy must be mixed with a curing agent which will cure the epoxyresin after a latent period such that the epoxy resin composition can beplaced in the disposal well. The epoxy resin composition should alsoinclude a liquid diluent for the epoxy resin such that the epoxy resincomposition will have a viscosity low enough for placing the epoxy resincomposition in the disposal well. The diluent must also be able toabsorb sufficient heat to prevent the epoxy resin composition fromprematurely setting while the epoxy is being mixed with the curing agentand diluent. Additionally, the diluent must become part of the curedepoxy resin composition such that the cured epoxy resin composition willoccupy substantially the same volume as the liquid epoxy resincomposition and such that the diluent will be included in the matrix ofthe epoxy resin composition to provide a hard, impermeable,corrosion-resistant solid.

A suitable liquid diluent has now been found and is a diluent or mixtureof diluents represented by the following general formula:

    C.sub.6 (R.sub.1).sub.6                                    (1)

wherein R₁ is hydrogen; a straight or branched chain alkyl radical; acycloparaffin radical, or a mixture thereof; wherein the alkyl andcycloparaffin radicals have within the range of about 1 to 10 carbonatoms; and further wherein at least one R₁ group is said alkyl orcycloparaffin radical.

Preferred liquid diluents are diluents or mixture of diluents repesentedby the following general formula:

    C.sub.6 H.sub.2 (R.sub.2).sub.4                            ( 2)

wherein R₂ is hydrogen; a straight or branched chain alkyl radical; acycloparaffin radical, or a mixture thereof; wherein the alkyl andcycloparaffin radicals have within the range of about 1 to 6 carbonatoms; and further wherein at leasst two R₂ groups are said alkyl orcycloparaffin radicals.

The most preferred liquid diluents are diluents or mixtures of diluentsrepresented by the following general formula:

    C.sub.6 H.sub.2 (R.sub.3).sub.4                            ( 3)

wherein R₃ is hydrogen; a straight or branched chain alkyl radicalhaving within the range of about 1 to 3 carbon atoms, or mixturesthereof; and further wherein at least two R₃ groups are said alkylradicals.

Examples of such suitable liquid diluents include but are not limited totoluene, ethylbenzene, n-propylbenzene, isopropylbenzene,n-butylbenzene, isobutylbenzene, cyclohexylbenzene, n-hexylbenzene,o-xylene, m-xylene, p-xylene, o-diethylbenzene, m-diethylbenzene,p-diethylbenzene, 2-chloro-p-xylene, o-diisopropylbenzene,m-diisopropylbenzene, p-diisopropylbenzene, 2-nitro-p-xylene, p-cymene,m-cymene, o-cymene, durene, isodurene, 1,2,3-trimethylbenzene,1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, 1,3,5-triethylbenzene,1,2,4-triethylbenzene, o-dibutylbenzene, m-dibutylbenzene,p-dibutylbenzene, penta-methylbenzene, 1-pentyl-3-ethylbenzene,p-pentyltoluene, 1-hexyl-3-isobutylbenzene, m-hexyltoluene,1-heptyl-3-isopropylbenzene, p-heptyltoluene, 1-heptyl-3-ethylbenzene,1-octyl-3-butylbenzene, 1-octyl-3-propylbenzene, p-octyltoluene,1-nonyl-3-ethylbenzene, p-nonyltoluene, 1-dodecyl-3-ethylbenzene,p-isodecyltoluene, and 1-decyl-3-isotridecylbenzene.

Suitable epoxy resins are thermosetting resins based on the reactivityof the epoxide group. Epoxy resins made from epichlorohydrin andbisphenol A (p,p'-isopropylidenediphenol) are readily available and areparticularly suitable for producing a pumpable resin composition curableto an impermeable, high strength solid. Suitable epoxy resins made fromepichlorohydrin and bisphenol A are liquid epoxy resins having molecularweights of about 200 to 1000 and preferably about 300 to 500 and haveone gram equivalent of epoxide per about 100 to 1000 grams of epoxyresin. An epoxy resin made from epichlorohydrin and bisphenol A which isparticularly useful has one gram equivalent of epoxide per about 150 to200 grams of the epoxy resin, an average molecular weight of about 400,and a viscosity at 25°C of about 100 to 200 poises.

suitable curing agents for epoxy resins to form a composition which willcure after a latent period to a hard, impermeable solid includehardeners and mixtures of hardeners and accelerators. Useful hardenersfor curing epoxy resin at temperatures of less than about 180°F includebut are not limited to polyamides or condensation products of fatty oraliphatic polycarboxylic acid which preferably contain at least sevencarbon atoms between the carboxyl groups and an aliphatic polyamine.Suitable polyamide hardening agents are derived from dimerized linoleicacid and ethylenediamine or diethyltriamine. Other fatty polyamidessuitable for curing epoxy resin are derived from a mixture of polymericfatty acids and dimerized rosin or from dimerized soybean-oil fattyacid. Commercial fatty polyamides are amber-colored thermoplasticcompounds with molecular weights up to about 10,000 which have aminevalues of about 50 to 400. This amine value is expressed as the numberof milligrams of KOH which is equivalent to the base content of one gramof fatty polyamide as determined by titration with hydrochloric acid.

An accelerator in combination with the hardener may also be useful toincrease the reactivity of the hardener. Useful accelerators include butare not limited to paradimethylaminomethyl phenol,ortho-dimethylaminomethyl phenol, 2,4,6-tri(dimethylaminomethyl)phenol,benzyldimethylamine, or mixtures thereof.

A polyamide hardener is particularly useful for curing epoxy resin andmay be used at a concentration within the range of about 10 to 30 andpreferably about 17 to 25 parts by weight polyamide hardener per 100parts by weight epoxy resin. The polyamide hardener is preferably mixedwith the epoxy resin at a concentration lower than the stoichiometricconcentration to increase the length of the latent period.

A particularly useful accelerator for use with the polyamide hardener is2,4,6-tri(dimethylaminomethyl)phenol This accelerator is useful withinthe concentration range of about 1 to 5 parts by weight accelerator per100 parts by weight epoxy resin.

At temperatures above about 150°F, a hardener of the carboxylic acidanhydride type is useful. Suitable carboxylic acid anhydride typehardeners include but are not limited tomethyl-bicyclo[2.2.1]heptene-2,3-dicarboxylic anhydride isomers(marketed by the Allied Chemical Company as Nadic Methyl Anhydride),chlorendic anhydride, phthalic anhydride, pyromellitic dianhydride,succinic anhydride, dodecenylsuccinic anhydride, maleic anhydride,hexahydrophthalic anhydride and mixtures thereof.

Nadic Methyl Anhydride is a particularly useful hardener for use attemperatures above about 150°F and is useful within the concentrationrange of about 60 to 130 and preferably about 90 to 110 parts by weightNadic Methyl Anhydride per 100 parts by weight epoxy resin.

A particularly useful accelerator for use with the Nadic MethylAnhydride hardener is 2,4,6-tri-dimethylaminomethyl)phenol. Thisaccelerator is useful within the concentration range of about 1 to 10parts by weight accelerator per 100 parts by weight epoxy resin. Otheraccelerators are also useful.

A solid diluent is also useful in this epoxy resin composition. Thesolid diluent reduces the cost of an epoxy resin composition and hasbeen found to increase the shear strength and compressive strength of anepoxy resin composition. Additionally, solid diluents minimize theshrinkage of an epoxy resin composition on curing. Silica ground toabout 200 to 325 mesh (U.S. Standard Sieve Series) has sufficientsurface area such that it will remain suspended in an epoxy resincomposition and can be added in sufficient concentrations tosignificantly dilute the epoxy resin composition. The addition of soliddiluent does increase the viscosity of the epoxy resin composition.Therefore, the maximum concentration of solid diluent is determined bythe viscosity of the resin composition to which the solid diluent isadded. Generally, solid diluent can be added until the viscosity of theepoxy resin composition is increased to about 50 poises and preferablyto less than about 30 poises which is the maximum viscosity which canreadily be placed in a well bore penetrating a subterranean formation.Other finely divided particles which are not reactive with thecomponents in the epoxy resin composition are also useful.

An epoxy resin composition containing epoxy resin and the aromaticdiluent hereinabove described is useful for sealing the annular spacebetween a conduit traversing a well bore penetrating a subterraneanformation and the well bore. This epoxy resin composition cures to ahard, impermeable solid which seals the annular space to isolate thezones traversed by the well bore, thus permitting the selective use of adesired zone.

This epoxy resin composition is resistant to degradation by manychemicals contained in liquid waste which is disposed of in subterraneanformations and is particularly useful for completing well borespenetrating subterranean formations and used for the disposal of liquidwaste.

An epoxy resin composition curable to a hard, impermeable,corrosion-resistant solid, which is particularly suitable for completinga well bore penetrating a subterranean formation, is a mixture of epoxyresin, liquid diluent, curing agent and solid diluent. The epoxy resinis made from epichlorohydrin and bisphenol A and has one gram equivalentof epoxide per about 150 to 200 grams of epoxy resin, an averagemolecular weight of about 400, and a viscosity at 25°C of about 100 to200 poises. The liquid diluent is selected from the group consisting ofliquid diluents or mixtures of liquid diluents represented by thefollowing general formula:

    C.sub.6 H.sub.2 (R.sub.3).sub.4                            ( 3)

wherein R₃ is hydrogen; a straight or branched chain alkyl radicalhaving within the range of about 1 to 3 carbon atoms, or mixturesthereof; and further wherein at least two R₃ groups are said alkylradicals.

The solid diluent is silica ground to about 200 to 325 mesh (U.S.Standard Sieve Series). A polyamide hardener is used as a curing agentfor the epoxy resin compositions cured at temperatures of less thanabout 160°F and Nadic Methyl Anhydride hardener is used for epoxy resincompositions cured at temperatures of greater than about 150°F. Thepolyamide is a commercial polyamide having an amine value of about 330to 360 and a viscosity at 25°C of about 40,000 to 60,000 centipoises.When epoxy resin compositions are cured at temperatures requiringaccelerators in combination with the hardening agent, they may beincluded in the resin composition. The polyamide hardener would beincluded in the epoxy resin composition at a concentration of about 17to 25 parts by weight polyamide hardener per 100 parts by weight epoxyresin while the Nadic Methyl Anhydride hardener is included in the resincomposition at a concentration of about 90 to 110 parts by weight NadicMethyl Anhydride hardener per 100 parts by weight epoxy resin. The epoxyresin composition includes about 20 to 40 parts by volume liquid diluentand about 60 to 80 parts by volume epoxy resin to produce 100 parts byvolume of the epoxy resin-diluent mixture. The epoxy resin composition,including epoxy resin, liquid diluent and curing agent, is mixed with100 to 170 parts by weight solid diluent per 100 parts by weight of theepoxy resin composition to form an epoxy resin composition which iscurable to a hard, impermeable, corrosion-resistant solid.

The epoxy resin composition described herein is suitable for manyapplication where it is desirable to place a liquid composition which iscurable to a hard, impermeable, corrosion-resistant solid. Additionally,this epoxy resin composition will bond to a wide variety of surfacesincluding, but not limited to, subterranean formations, salt and metal.These properties are desirable for a composition for groutingapplications including the impregnation and hardening of soils and therendering of dams, dikes, retaining walls, canal bank walls and thelike, impervious to the passage of liquids. Other applications for thiscomposition include the stabilization of load-bearing members such aspiles and foundations in loose earth formations, repairing leaks in wellcasing and repairing cement to prevent communication between zones.

The following examples are presented to illustrate a pumpable epoxyresin composition. However, the invention is not limited thereto.

EXAMPLE I

The strength of an epoxy resin composition is determined. The epoxyresin composition is prepared by mixing an epoxy resin with a liquidaromatic diluent, a hardener, and an accelerator. The liquid epoxy resinhas a viscosity of about 100 to 200 poises at 25°C; a molecular weightof about 300 to 500; and having one gram equivalent of epoxide per about150 to 200 grams of epoxy resin. The aromatic diluent has a viscosity ofabout 1 to 3 centipoises at 25°C; a boiling range of about 360°F to390°F, and contains a mixture of aromatic diluents which includearomatic diluents represented by the following general formulae: C₆ H₄(CH₃)(C.sub. 3 H₇) C₆ H₃ (CH₃)(C.sub. 2 H₅)₂ ; C₆ H₂ (CH₃)(C.sub. 2H₅)(C.sub. 3 H₇); and C₆ H₂ (CH₃)₂ (C₂ H₅). The polyamide is acommercial polyamide having an amine value of about 330 to 360 and aviscosity at 25°C of about 40,000 to 60,000 centipoises. The epoxy resinand aromatic diluent are mixed at 64 parts by weight epoxy resin and 36parts by weight aromatic diluent per 100 parts by weight of the epoxyresin-aromatic diluent mixture. The epoxy resin composition is 86 partsby weight epoxy resin-aromatic diluent mixture, 11 parts by weightpolyamide hardener, and 3 parts by weight2,4,6-tri(dimethylaminomethyl)phenol per 100 parts by volume epoxy resincomposition. The resulting epoxy resin composition has a viscosity ofabout 100 centipoises at 80°F.

The compressive strength of the epoxy resin composition is determined bycasting the epoxy resin composition into 2 inch cubes. The cubes arecured 48 hours at 120°F before testing. The cubes have a compressivestrength of about 6650 PSI.

The bond strength of the epoxy resin composition to salt crystals isdetermined by casting the epoxy resin composition between two 2 inch × 2inch × 0.666 inch salt crystals to form a 2 inch cube. The cube is curedeight hours at 140°F before testing the cubes for bond strength bymeasuring the shear strength of the cube at the interface of the epoxyresin composition and salt crystal. The shear strength is about 940 PSI.

The compressive strength and shear strength of the epoxy resincomposition mixed with 150 parts by weight of about 200 to 325 mesh(U.S. Standard Sieve Series) silica per 100 parts by volume epoxy resinis determined by the same procedure. The silica increases the viscosityof the epoxy resin composition to about 3550 centipoises at 30°F. Themixture of silica and the epoxy resin composition has a shear strengthof about 1875 PSI and a compressive strength of about 8440 PSI.

A 2 inch cube of the salt crystal has a shear strength of about 750 PSIand a compressive strength of about 4450 PSI.

The tensile strength of the epoxy resin composition after curing 48hours at 120°F is about 650 PSI and the tensile strength of the epoxyresin cmposition mixed with silica is about 1000 PSI. The hydraulic bondof the epoxy resin composition to steel pipe after curing 48 hours at120°F is about 3100 PSI and the hydraulic bond of the epoxy resincomposition mixed with silica is greater than 5000 PSI.

The compressive strength of the epoxy resin composition is alsodetermined by injecting the epoxy resin composition into a brine-wetsand pack to fill the spaces between the sand particles. After curing 48hours at 120°F the epoxy resin composition impregnated sand pack has acompressive strength of about 7298 PSI.

EXAMPLE II

The strength of an epoxy resin composition is determined. The epoxyresin composition is prepared by mixing an epoxy resin mixture includinga hardener, accelerator, and the liquid epoxy resin described in ExampleI with the aromatic diluent described in Example I. The epoxy resin andaromatic diluent are mixed at 64 parts by weight epoxy resin and 36parts by weight aromatic diluent per 100 parts by weight of the epoxyresin-aromatic diluent mixture. The epoxy resin composition is 61 partsby weight liquid epoxy resin-aromatic diluent mixture, 38 parts byweight Nadic Methyl Anhydride hardener, and one part by weight2,4,6-tri(dimethylaminomethyl) phenol accelerator per 100 parts byweight of the epoxy resin composition. The resulting epoxy resincomposition has a viscosity of about 86 centipoises at 80°F.

The epoxy resin composition is tested by the procedures described inExample I. After curing 48 hours at 120°F, the epoxy resin compositionhas a compressive strength of about 8560 PSI and a hydraulic bond tosteel pipe of greater than 5000 PSI.

EXAMPLE III

Aromatic diluents are mixed in a curable epoxy resin formulation todetermine the viscosity of the curable epoxy resin formulationcontaining the diluent, the temperature increase of the epoxy resinformulation on curing, the compressive strength of the cured epoxy resinformulation and the weight loss of the cured epoxy resin formulation dueto loss of diluent from the cured epoxy resin formulation. The curableepoxy resin composition is a mixture of liquid epoxy resin with 19.8parts by weight polyamide hardener, 5.45 parts by weight accelerator,and 19.8 parts by weight aromatic diluent per 100 parts by weight liquidepoxy resin.

The liquid epoxy resin, polyamide hardener and accelerator are describedin Example I. The aromatic diluent is shown on Table I.

The curable epoxy resin composition is mixed at room temperature and theviscosity of the epoxy resin composition is measured immediately aftermixing the composition. The viscosity measurements shown on Table I aremade on a Brookfield Model LVF Viscometer with a No. 2 spindle. The peakexotherm was measured by placing 100 grams of the curable epoxy resincomposition in an insulated container and measuring the temperatureincrease with a maximum reading thermometer. The weight loss of thecured epoxy composition on a cylindrical sample of the cured epoxy resincomposition having a diameter of 0.86 inch and a length of 2 inches. Theepoxy resin composition is cured for 24 hours in a 120°F water bath,removed from the molds and cooled to room temperature before measuringthe weight of the sample to the nearest one-hundredth gram. The samplesare then cured at 150°F and under a vacuum of 21-23 mmHg for 24 hours.The samples are then cooled to room temperature and the weightdetermined to the nearest one-hundredth gram. The compressive strengthof the cured epoxy resin composition of a 2 inch section of the epoxyresin composition which is cast in a mold having an internal diameter of1 3/16 inches and a length of 5 inches.

The data on Table I indicates that the aromatic diluents disclosed inthis application produces a liquid epoxy resin composition with aviscosity such that the epoxy resin composition can be pumped and absorbsufficient heat to reduce the exotherm of the epoxy resin compositionupon curing. These aromatic diluents also produce a cured epoxy resincomposition with a high strength and a cured epoxy resin compositionwith the diluent included in the matrix of the epoxy resin compositionto provide a hard, impermeable, corrosion-resistant solid which occupiessubstantially the same volume as the liquid epoxy resin composition.

This data also indicates that these diluents reduce the viscosity of theepoxy resin compositions and that the substitutions on the aromaticnucleus are important for high strength, low weight loss from the curedepoxy resin composition. It is seen that the highest strength epoxyresin compositions and the cured epoxy resin compositions with thelowest weight loss are the epoxy resin compositions prepared witharomatic diluents having at least two alkyl radicals and having about 1to 3 carbon atoms in the alkyl radical.

                                      TABLE I                                     __________________________________________________________________________    Epoxy Resin Compositions Containing Aromatic Diluents                                     Viscosity                                                                            Peak Exotherm                                                                          Compressive Strength                                                                      Weight Loss                           Diluent     (Centipoise)                                                                         (Δ t °F)                                                                  (PSI)       (Parts by Weight).sup.1               __________________________________________________________________________    Benzene     42.5   10       2724        24.45                                 Toluene     37.5    8       4785        24.07                                 Xylene (mixed)                                                                            46.5     13.5   5202        20.06                                 o-xylene    65     14       6082        16.7                                  m-xylene    49.5     14.5   5169        16.1                                  p-xylene    40       13.5   5431        20.34                                 Mesitylene  95     12       5543        11.86                                 Durene      slurry 45       4425        --                                    Isodurene   160    18       7058        7.7                                   penta-methylbenzene                                                                       167    24       7344        2.2                                   Ethylbenzene                                                                              46     13       4637        18.41                                 Diethylbenzene (mixed)                                                                    70     15       7697        7.3                                   Butylbenzene                                                                              51     10       6500        26.89                                 p-cymene    85     15       8817        5.9                                   2-chloro-p-xylene                                                                         109    16       5711        25.43                                 2-nitro-p-cymene                                                                          284    20       6772        21.14                                 1-methylnaphthalene                                                                       370    25       7336        9.9                                   Styrene     40     4        2812        23.6                                  Cinnamaldehyde                                                                            1050   --       none        --                                    Mixed diluent.sup.2                                                                       107    16       7193        10.81                                 Dialkyl benzene.sup.3                                                                     3075   56       10,259      3.0                                   __________________________________________________________________________     .sup.1 Parts by weight per 100 parts by weight of cured epoxy resin           composition.                                                                  .sup.2 A commercial mixed diluent containing diluents represented by the      following general formulae: C.sub.6 H.sub.4 (CH.sub.3) (C.sub. 3 H.sub.7)     C.sub.6 H.sub.3 (CH.sub.3) (C.sub.2 H.sub.5).sub.2, C.sub.6 H.sub.3           (CH.sub.3).sub.2 (C.sub.2 H.sub.5), and C.sub.6 H.sub.3 (CH.sub.3)            (C.sub.2 H.sub.5) (C.sub.3 H.sub.7).                                          .sup.3 A commercial dialkyl benzene diluent represented by the following      general formula:                                                         

It will be apparent that many widely different embodiments of thisinvention may be made without departing from the spirit and scopethereof, and, therefore, it is not intended to be limited except asindicated in the appended claims.

What is claimed is:
 1. An epoxy resin composition for sealing asubterranean zone penetrated by a well bore containing about 20-40 partsby volume of an aromatic diluent selected to provide a pumpable epoxyresin composition wherein said aromatic diluent is selected to preventpremature setting by absorbing heat and to provide a cured epoxy resincomposition occupying substantially the same volume as said pumpableepoxy resin; wherein said pumpable epoxy resin composition is curable toa high strength, impermeable matrix with a weight loss of less thanabout 20 parts per 100 parts by weight of said pumpable epoxy resincomposition; said pumpable epoxy resin composition comprising an epoxyresin, a curing agent and said selected aromatic diluent; wherein saidselected aromatic diluent is at least one or a mixture contaning anaromatic hydrocarbon of the general formual C₆ (R₁)₆ wherein R₁ ishydrogen, a straight or branched chain alkyl radical, a cycloparaffinradical or a mixture thereof; wherein each alkyl and cycloparaffinradical has about 1-10 carbon atoms; and further wherein at least one R₁group is radical.
 2. An epoxy resin composition of claim 1 for sealing asubterranean zone penetrated by a well bore containing about 20-40 partsby volume of an aromatic diluent selected to provide a pumpable epoxyresin composition wherein said aromatic diluent is selected to preventpremature setting by absorbing heat and to provide a cured epoxy resincomposition occupying substantially the same volume as said pumpableepoxy resin; said pumpable epoxy resin composition comprising an epoxyresin, a curing agent in a concentration less than stoichiometric toincrease the latent period of said pumpable epoxy resin composition andsaid selected aromatic diluent.
 3. An epoxy resin composition of claim 2for sealing a subterranean zone penetrated by a well bore comprising apumpable epoxy resin composition curable to a high strength, impermeablematrix; said pumpable epoxy resin composition comprising a mixture ofepoxy resin, a curing agent and an aromatic diluent; said aromaticdiluent being selected to provide a pumpable resin composition, preventpremature setting and produce a cured epoxy resin composition occupyingsubstantially the same volume as said pumpable epoxy resin composition;said aromatic diluent being at least one or a mixture containing anaromatic hydrocarbon of the general formula C₆ H₂ (R₁)₄ wherein each R₁is independently hydrogen, a straight or branched chain alkyl radical; acycloparaffin radical, or a combination of said radicals, wherein eachof said radicals have about one to ten carbon atoms and wherein at leastone R₁ is said radical.
 4. An epoxy resin composition of claim 2 forsealing a subterranean zone penetrated by a well bore wherein saidaromatic diluent comprises at least one or a mixture of toluene,ethylbenzene, n-propylbenzene, isopropylbenzene, n-butylbenzene,isobutylbenzene, cyclohexylbenzene, n-hexylbenzene, o-xylene, m-xylene,p-xylene, o-diethylbenzene, m-diethylbenzene, p-ethylbenzene,2-chloro-p-xylene, o-diisopropylbenzene, m-diisopropylbenzene,p-diisopropylbenzene, 2-nitro-p-xylene, p-cymene, m-cymene, durene,isodurene, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene,1,3,5-trimethylbenzene, 1,3,5-triethylbenzene, 1,2,4-triethylbenzene,o-dibutylbenzene, m-dibutylbenzene, p-dibutylbenzene,penta-methylbenzene, 1-pentyl-3-ethylbenzene, p-pentyltoluene,1-hexyl-3-isobutylbenzene, m-hexyltoluene, 1-heptyl-3-isopropylbenzene,p-heptyltoluene, 1-heptyl-3-ethylbenzene, 1-octyl-3-butylbenzene,1-octyl-3-propylbenzene, p-octyltoluene, 1-nonyl-3-ethylbenzene,p-nonyltoluene, 1-dodecyl-3-ethylbenzene, p-isodecyltoluene and1-decyl-3-isotridecylbenzene.
 5. An epoxy resin composition of claim 2for sealing a subterranean zone penetrated by a well bore wherein saidaromatic diluent comprises a mixture of aromatic hydrocarbons having aviscosity of about 1-3 centipoises at 25° C and boils at about 360°-390°F and 760 millimeter pressure.
 6. An epoxy resin composition of claim 2for sealing a subterranean zone penetrated by a well bore wherein saidaromatic diluent comprises at least one or a mixture containinghydrocarbons represented by the formulae: C₆ H₄ (CH₃)(C.sub. 3 H₇); C₆H₃ (CH)₃ (C₂ H₅)₂ ; C₆ H₂ (CH₃)(C.sub. 2 H₅)(C.sub. 3 H₇); and C₆ H₂(CH₃)₂ (C₂ H₅).
 7. An epoxy resin composition of claim 2 wherein saidpumpable epoxy resin composition contains a solid diluent to increasethe shear strength and compressive strength of the cured epoxy resincomposition.
 8. An epoxy resin composition of claim 2 wherein said epoxyresin is derived from epichlorohydrin and p,p'-isopropylidenediphenol,has one gram equivalent of epoxide per about 150-200 grams of said epoxyresin, has a molecular weight of about 400 and has a viscosity of about100-200 poises at 25° C; wherein said pumpable epoxy resin compositionincludes about 20-40 parts by volume of said aromatic diluent per 100parts by volume of said pumpable epoxy resin composition.
 9. An epoxyresin composition of claim 2 for sealing a subterranean zone whereinsaid aromatic diluent is at least one or a mixture containing anaromatic hydrocarbon of the general formula C₆ H₂ (R₂)₄ ; wherein eachR₂ is independently hydrogen, a straight or branched chain alkylradical, a cycloparaffin radical or a combination of said radicalswherein each radical has about one to six carbon atoms and wherein atleast two R₂ groups are said radicals.
 10. An epoxy resin composition ofclaim 2 for sealing a subterranean zone penetrated by a well borewherein the epoxy resin is derived from epichlorohydrin andp,p'-isopropylidenediphenol, has about one gram equivalent of epoxideper about 150-200 grams of said epoxy resin, has a molecular weight ofabout 400 and has a viscosity of about 100-200 poises at 25° C; whereinsaid pumpable epoxy resin composition includes about 20-40 parts byvolume of said aromatic diluent per 100 parts by volume of said pumpableepoxy resin composition; wherein said aromatic diluent is at least oneor a mixture containing an aromatic hydrocarbon of the general formulaC₆ H₂ (R₃)₄ wherein each R₃ radical is independently hydrogen, astraight or branched chain alkyl radical, or a combination of saidradicals wherein each radical has about one to three carbon atoms,wherein at least two R₃ groups are said radicals, wherein said aromaticdiluent has a viscosity of about one to three centipoises at 25° C andboils at about 360°-390° F at 760 millimeters pressure and wherein saidpumpable epoxy resin composition contains said curing agent in aconcentration less than the stoichiometric concentration for said epoxyresin.
 11. An epoxy resin composition of claim 2 for sealing asubterranean zone penetrated by a well bore wherein said zone is aportion of the annulus defined by said well bore and a conduit withinsaid well bore; wheren the epoxy resin is derived from epichlorohydrinand p,p'-isopropylidenediphenol, has about one gram equivalent ofepoxide per about 150-200 grams of said epoxy resin, has a viscosity ofabout 100-200 poises at 25° C; wherein said pumpable epoxy resincomposition includes about 20-40 parts by volume of said aromaticdiluent per 100 parts by volume of said pumpable epoxy resincomposition; wherein said aromatic diluent is at least one or a mixturecontaining an aromatic hydrocarbon of the general formula C₆ H₂ (R₁)₄wherein each R₁ radical is independently hydrogen, a straight orbranched chain alkyl radical, a cycloparaffin radical or a combinationof said radicals, wherein each radical has about one to ten carbonatoms, wherein at least two R₁ groups are said radicals and wherein saidpumpable epoxy resin contains a solid diluent to increase shear strengthand compressive strength of the cured epoxy resin composition andwherein said pumpable epoxy resin composition contains said curing agentin a concentration less than the stoichiometric concentration for saidepoxy resin.
 12. In a composition for sealing a subterranean zonepenetrated by a well bore comprising a pumpable epoxy resin composition,the improvement of including in said pumpable epoxy resin composition anaromatic diluent selected to produce cure to an epoxy resin compositionhaving a high strength, impermeable matrix occupying substantially thesame volume as said pumpable epoxy resin composition, with a weight lossof less than about 20 parts per 100 parts by weight of said pumpableepoxy resin composition, thereby sealing said zone.
 13. A composition ofclaim 2 wherein said pumpable epoxy resin composition contains a soliddiluent to increase the shear strength and compressive strength of thecured epoxy resin composition.